PS D:\> cd gs:\
cd : Cannot find drive. A drive with the name 'gs' does not exist.
PS D:\> Get-GcsBucket
PS D:\> cd gs:\mybucket
Why I can not change drive to gs:\ before Get-GcsBucket?
PS gs:\mybucket> mkdir NewFolder
PS gs:\mybucket> cd .\NewFolder
cd : Cannot find path 'gs:\mybucket\NewFolder' because it does not exist.
PS gs:\mybucket> ls
Name Size ContentType TimeCreated Updated
---- ---- ----------- ----------- -------
NewFolder
Why I can not change directory?
Unlike Cmdlets and Functions, Providers and the drives they add can not be discovered until the module they are part of is imported into the current PowerShell session. This can be done explicitly with Import-Module, or implicitly by calling a Cmdlet or Function that is discoverable, such as Get-GcsBucket.
Why are Cmdlets discoverable but drives aren't? Because the module manifest lists the Cmdlets, but does not have an entry for drives, and also because the Cmdlet names are stored in assembly metadata (as attributes) that can be read without loading the assembly, while the drive comes directly from code that can only be run after loading the assembly.
It looks like a bug, but I have not been able to reproduce it. If you can provide more information, I encourage you to submit an issue on the Google Cloud Powershell issues page.
I'm going to guess this is a bug in the Cloud Tools for PowerShell module.
When you launch PowerShell it loads a manifest file (GoogleCloud.psd1) which provides a declaration for every cmdlet that the module contains. This allows PowerShell to delay loading the actual cmdlets assembly until it is actually needed. And thereby speeding up startup time considerably.
The actual list of which cmdlets are found in the module is determined as part of the build and release process. Some info here.
Anyways, that manifest is not declaring the existence of the Cloud Storage PowerShell provider (the cd gs:\ bits.) So PowerShell doesn't know that it exists until after it loads the GoogleCloud PowerShell module, which is done after you invoke Get-GcsBucket (or I assume any cmdlet in the module) at least once.
